In various industries and applications, drilling of materials may be performed using solid twist drill designs. In the aerospace industry for example, to successfully drill the various metals used in the industry, solid twist drills provide desired capabilities, such as being precise. This style of tooling may have through coolant capability and the coolant outlets typically exit on the clearance angle of the cutting geometry at the nose of the tool. As chips are created during the drilling cycle, the flute helix and coolant pressure work to evacuate chips through the flutes. Once the chips and coolant exit the hole, they are released into the environment.
In some applications and environments, the components may require the use of portable drilling machines to allow drilling of multiple holes at different locations. For example, in the aerospace industry, the components may be very large and require portable drilling machines that can be moved to the different hole locations on the component. The portable drilling machines are compact and do not provide any enclosure to isolate the drilling process from the outside environment. This results in the release of chips and coolant into the environment when utilizing solid twist drills. Because the chips evacuated from the hole are not contained, additional process time is required in order to remove the chips and coolant from the component and drilling environment. Additionally, failure to contain the chips and coolant flow may cause health and safety hazards for drill operators.
Additionally, the generation of chips during the drilling of various materials requires the chips to be conveyed away from the cutting features of the drill, or the chips can impede the drilling process and/or cause damage to the drill. For certain materials, such as composite materials including carbon fiber reinforced plastic (CFRP), for example, there have been developed drilling systems which use a vacuum to remove the large quantities of fine chips created when drilled. Without effective removal of the chips thus generated, chip compaction often occurs, reducing the drill's ability to cut, increasing the generation of heat, and reducing the life of the drill. The cooling effect and force originating from a vacuum applied to the drill is sufficient for providing the needed heat dissipation and chip extraction in CFRP material. This results in a reliable drilling process for CFRP that utilizes an applied vacuum.
A need still exists for a reliable vacuum drilling system that can perform in metal drilling applications. The properties of various metals can be considerably different from one another, and are different than the properties of CFRP. For example, in materials such as titanium and aluminum, it would be desirable to facilitate removal of chips using an applied vacuum, but with metallic materials, the prior vacuum systems for CFRP materials are not designed to be used on such materials. It would be worthwhile to provide a vacuum drilling system which may be used for metallic or other materials, to effectively remove chips during the drilling process.
In addition to requiring effective chip removal, it is also desirable that the drilling operation be precise, to provide repeatable machining to close tolerances and desired specifications.
In the machining operation to drill metallic, composite or other materials, it would be desirable to provide a drilling system and methods to effectively remove chips formed during the drilling operation. There is also a need to provide a drilling system and methods to effectively provide coolant to the cutting surfaces while allowing for the effective removal of chips formed during the drilling operation.